QB Matt Cassel

Some feel he will one day bring the Chiefs a lot of success in the postseason, while others believe he will struggle against challenging teams.

Although this will be Cassel's seventh season in the league, it will be only his fourth season as an active quarterback. Prior to taking over for Tom Brady, Cassel did not start a game since high school.

It's clear that Cassel has a lot to learn, but with a good 2010 season under his belt, he'll walk into this season with a higher level of confidence.

If Cassel is injured and misses multiple games, we'll either see rookie Ricky Stanzi or Brodie Croyle take the starting quarterback job, depending on who Scott Pioli and Todd Haley want to keep.

This will be Cassel's third season in Kansas City.

Fans will keep an eye on him to see if he can continue to make progress as a Chief after helping them have the biggest turnaround in franchise history last season.

WR/RB/KR Dexter McCluster

Out of all the rookies drafted by Kansas City last year, none received more hype than Dexter McCluster during training camp.

McCluster made a great first impression when he returned a punt for a touchdown in Week 1 against San Diego.

Soon after, fans realized he did it against a team that struggled on special teams all season.

Two weeks later, against San Francisco, McCluster made a nice catch and ran for 31 yards for a touchdown.

After that, McCluster never found himself in the end zone with the football in his hands.

Despite not finding the end zone in Week 7 against Jacksonville, McCluster contributed to the Chiefs' ground game, as he earned 28 of 236 rushing yards.

McCluster was also used through the air as he came away with five catches for 41 yards, giving him 69 yards of total offense on nine touches. After helping the Chiefs move the football, he left the game early with a high ankle sprain. The injury would force him to miss the next five games.

McCluster's return wasn't as memorable as many had expected.

He blames his disappointing rookie season on his injury and says he's ready to have a better season in an interview with the Kansas City Star.

McCluster has the ability to make big plays due to his speed.

He knows he needs to stay healthy in order to find that high level of success.

WR Dwayne Bowe

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Dwayne Bowe's season was full of emotional roller coasters.

Bowe's talent seemed to be erased after dropping multiple passes. Bowe received a heavy load of criticism in Week 5, when he dropped what could have been the go-ahead touchdown against Indianapolis on the road.

The Chiefs eventually lost the game.

The fans and the media were ready to label Bowe as a first-round bust.

Some hoped that the Chiefs could find a trade partner before the deadline arrived. However, Haley saw something in Bowe that no one else saw.

Haley has worked with many elite wide receivers and knew Bowe could join the list of key receivers Haley has coached.

One week later, Bowe immediately turned his career around by scoring two touchdowns in a loss against Houston.

In 2010, Bowe had a total of five multi-touchdown games and caught at least one touchdown in seven consecutive games. He racked a league-high 15 touchdowns through the air last season.

That is the most touchdowns in a season for a receiver since Randy Moss in 2007. For the first time in his career, Bowe earned Pro Bowl and All-Pro honors.

This year, Bowe must prove he can repeat and continue to play at a high level.

Fifteen touchdowns in back-to-back seasons may be a lot to ask for, but keep in mind, the Chiefs relied on Tony Moeaki and Jamaal Charles in the passing game more than Chris Chambers.

Now that Bowe is coming off of a successful season, he must carry that over in 2011 as he mentors rookie Jonathan Baldwin.

Bowe will be considered a key player and a leader for the first time in his career. Players will look up to Bowe and hope to learn from him to help carry the load.